On Tuesday, Paris Saint-Germain's 3-2 win over Barcelona breathed a fresh lease of life into Group F, Luis Enrique's first defeat as manager of the Camp Nou outfit and another reason to believe PSG are on the cusp of even bigger things.
Manchester City, meanwhile, were halted by Roma 1-1 at the Etihad Stadium, Chelsea faring more fruitfully in their trip to face Sporting Lisbon, coming out of the Portuguese capital with a 1-0 triumph.
That being said, there were reasons to keep one's eyes peeled across the continent as drama unfolded in every fixture before Wednesday brings another onslaught ...